With Van Persie on the ground, a ball struck by Williams hit the striker on the head. United boss Sir Alex Ferguson was incensed, saying: "Robin van Persie is lucky to be alive. It was a disgraceful act from their player and he should be banned by the FA. Robin could have had a broken neck."

Williams, who was booked by referee Michael Oliver, has insisted it was not intentional and wants to move on.

"I understand why Van Persie was angry," Williams told Sky Sports. "I've kicked the ball away in frustration, but I wasn't trying to hit him in the head.

"I tried to say sorry, but he wasn't having it. I haven't spoken to him since the game and I didn't shake hands afterwards - but only because I didn't see him. As far as I'm concerned it's no big deal.

"If I had tried to hit him on the head deliberately, I would have missed! It's not like I'm going to shoot and hit him square in the head like that."